目前為止，砷化鎵奈米線大多是成長在砷化鎵基板上，對於以分子束磊晶(MBE)技術在矽基板上成長砷化鎵奈米線的討論並不多。成長在矽基板上的砷化鎵奈米線，除了可探討光與電的特性外更可降低成本。有望結合高效能的Ⅲ-Ⅴ半導體奈米線和矽電晶體工業技術的兩種優點。
以VLS方式來成長砷化鎵奈米線的製程通常會以金當作催化劑，然而金的存在會造成深成缺陷而影響奈米線中電子電洞的傳輸行為。本實驗利用矽原生氧化層的孔洞及鎵液滴形成自我催化，經由VLS過程在矽基板上異質磊晶成長自催化的砷化鎵奈米線。
實驗中分別以矽和鈹兩元素當作n-type與p-type的摻雜，成功地在矽基板上成長了核殼結構的砷化鎵奈米線。且經由固定殼層生長時間、但變核層成長時間的條件下，得到了長度不同但直徑相近的奈米線。成長完成後，對試片進行旋塗絕緣層、蝕刻絕緣層、沉積導電層等步驟。之後將整組試片進行電性量測，過程中探討的奈米線長度、蝕刻時間、以及不同導電層對I-V特性的影響。結果發現整體砷化鎵奈米線具有二極體之特性，此結構有望能發展成為太陽能電池元件。

To data, GaAs nanowires(NWs) have been mostly grown on the GaAs substrates, while, far fewer studies have been on the synthesis of GaAs NWs on Si substrates by molecular beam epitaxy (MBE). The growth of GaAs NWs on Si offers the possibility to investigate the optical and electrical properties of the nanowires; moreover, it is expected to combine advantages high efficient III-V materials and low-cost silicon technology.
Traditionally, fabrication of GaAs NWs has mainly relied on the use of gold as catalyst via the vapor-liquid-solid (VLS) mechanism. However, the incorporation of gold may generate deep level traps and degrade the electron and hole transport properties of the nanowires. In this work, so-called self-assisted method was employed to grow the GaAs NWs on (1 1 1)Si, where Ga droplets in the pinholes of Si native oxide were used to induce anisotropic growth.
We have successfully grown coaxial GaAs NWs on Si(111) substrates by MBE using Be and Si as the p-type and n-type dopants, respectively. During NW growth, we fixed the shell growth time and changed the core growth time. We found the lengths of the nanowires increase with core growth time, while the diameters of the nanowires remain almost constant.
All the GaAs core-shell NWs have been subjected to the following pn junction fabrication processes: insulator spin coating, insulator reactive-ion-etching, and conductive layer depositing. I-V properties of the as-fabricated nanowire pn devices were then investigated. We discussed the effect of the nanowire length, insulator etching condition, and types of conductive layer on the I-V properties of NW devices. We observed all fabricated NW devices have exhibited the properties of diode, suggesting their potential use as building blocks in solar cells.

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